1. Field of the Invention
This invention relates to a hand-held dispenser and more particularly to a hand-held dispenser for mixing water passing therethrough with a liquid chemical. Further, this invention relates to a hand-held dispenser which includes a backflow preventer should the dispenser be subjected to a backflow problem.
2. Description of the Related Art
Many types of dispensers have been previously provided which may be connected to the end of a water hose or the like wherein the dispenser introduces chemicals into the water flow so that a lawn or the like may be sprayed. Further, the dispensers of the prior art are also able to inject liquid chemicals into a water stream so that a mop bucket, etc., may be filled with water, detergent or other chemicals. In Applicant's earlier U.S. Pat. Nos. 7,237,728; 7,296,761; and 8,177,143 hand-held dispensers are disclosed which are able to conveniently and economically precisely control the rate of waterflow through the dispenser and to precisely control the metering of liquid chemicals in the precisely controlled flow of water.
Although the dispensers of Applicant's earlier patents have met with considerable success, Applicant has developed an improved hand-held dispenser which is convenient to use and which includes a backflow preventer which prevents the source of water from being contaminated should the dispenser be subjected to a backflow problem.